Cylinder grinding tool



April 4, 1944. c, A, FULMER- 2,345,930

CYLINDER GRINDING TOOL Filed Feb. 18, 1942 4 Sheets-Sheet 1 I INVENTOR/4 Charles A. Fuimei' flaw, I

Ap c. A. :FULMER 2,345,930

CYLINDER GRINDING TOOL Filed Feb. 18, 1942 4 Shegis-She'et 2 INVENTOR.

BY Charles A Fulmer M,

April 4, 1944. c A, FULMER 2,345,930

CYLINDER GRINDING TOOL "1196. Feb. 18, 1942 4 Sheets-Sheet 3 INVENT OR.

Charles A. Fulmer April 4, 1944. c. A. FULMER CYLINDER GRINDING TOOLFiled Feb. 18, 1942 4 Sheets-Sheet 4 in. I IIHI I' II/)1IIIIIIIIIIIIIIIIIIIH I INV ENT OR.

Charles .Fulmer M,1*!%@ Patented Apr. 4, 1944 UNITED STATES PATENTOFFICE CYLINDER GRINDING TOOL Charles A. 'Fulmer, Waukegan, Ill.,assignor to Automotive Maintenance Machinery 00., North Chicago, 111., acorporation of Illinois Application February 18, 1942, Serial No.431,348

17 Claims.-

My invention relates -to cylinder grinding tools and it has to doparticularly with a tool of the foregoing character well adapted forfactory production use.

One of the objects of my invention is to provide an improved cylindergrinding tool which is of simple and rugged construction, is inexpensiveto manufacture, is durable, is highly accurate in performance, and isadapted to greatly increase efficiency in the grinding of cylinders.

Another object is to provide improved means for quickly and easilygrinding cylinders to predetermined size under a substantially constantand predetermined pressure.

Still another object is to provide an expansible and contractiblecylinder grinding tool which is adapted to be automatically expandedduring the grinding operation and which is so constructed and arrangedas to reduce the chance of error to a minimum. In other words, myinvention contemplates a cylinder grinding tool adapted for Anadditional object is to provide pressure ad.- '1

justing mechanism of the foregoing character which embodies acompression spring adapted to bev loaded to variable extents forapplying variable unit stone pressures, which spring loading is effectedpositively and accurately by an adjust able element movable to andlatchable in a plurality of positions in each of which the spring isplaced under a predetermined load for effecting a predetermined unitstone pressure.

A further object is to provide a cylinder grindl ing tool having animproved form of rigid, cage- .like frame structure supporting abrasivecarriers for movement toward and from a cylinder wall to be ground.

A more specific object is to provide a cylinder grinding tool of theforegoing character wherein the abrasive carriers are supported againstdistortion during the grinding operation, thereby materially increasingthe life of the carriers, and abrasive members supported thereby.

Still another object is to provide improved means for determining theextent and range of the grinding operation, the arrangement being suchthat a single cylinder may be ground autotool shown in Fig.

of cylinders may be ground to the same size with a minimum of attentionon the part of the operator. 7

A more specific object is to provide a tool of the foregoing characterwherein the desired working load for the expanding spring is selectivelyeffected by a cam device adjustable to a plurality of positions in eachof which the expanding spring is compressed to a different extent foreffecting a different and predetermined unit stone pressure.

Other objects and advantages will become apparent as this descriptionprogresses and by reference to the drawings, wherein- Figure 1 is anelevational View of one form of cylinder grinding tool embodying myinvention, the tool being illustrated in position in a cylinder beforethe tool has been fully expanded into engagement with the cylinder wall;

Fig. 2 is a top plan view of the tool shown in Fig. 1;

Fig. 3 is a central vertical sectional view of the Fig. 3 is a sectiontaken substantially on line 3* 3 of Fig. 3;

Fig. 3 is a fragmental view of a portion of the spring loading camdevice shown in Figs. 1 and 3;

Fig. 4 is a bottom plan'view of the structure shown in Figs. 1 and 3;

Fig. 5 is a section taken substantially on line 5-5 of Fig. 3;

Fig. 6 is an assembly view of the spring loading cam device shown inFigs. 1 and 3;

Fig. 7 is a fragmental view of the structure shown in Fig. 3illustrating the spring loading cam device in a position such as may beemployed for initially grinding a cylinder to remove tool marks and highpoints;

Fig. 8 is a top plan view of the rotatable part of the cam device in theposition illustrated in Fig. '7;

Fig. 9 is a view similar to Fig. '7 illustrating the cam device in aposition for loading the expanding spring to a greater extent such asmay be maximum spring loading;

Fig. 12 is a top plan view of the rotatable part of the cam device inthe position shown in Fig.

Fig. 13 is a vertical sectional view of a modimatically to predeterminedsize and a plurality fled form of tool embodying my invention;

Fig. 14 is a partial elevational view of the structure shown in Fig. 13illustrating the tool driving means; and

Fig. 15 is a bottom plan view of the tool shown in Fig. 13, certainportions thereof being cut away to better illustrate the structure.

Although the tool shown in the drawings is well adapted for the grinding.of cylinders in the so-called production field, it is to be understoodthat it may also be used for grinding tools in the so-called servicefield. In use, the tool shown in Figs. 1 to 12, inclusive, is driven bya so-called honing or grinding machine (not shown) having a spindle (notshown) connected to a ball head on the tool forming part of a universaljoint. The ball head 20 is carried by a yoke member 21 connected to thetool body, which will now be described.

The tool body (Figs. 1-4) is of a rigid, framelike constructionincluding a pair of end plates 22 and 2-3 axially spaced apart andrigidly secured together by an annular series of posts 24 forming radialpassages which are mounted abrasive carriers 25. The lower ends of theposts 24 are riveted in the bottom plate 23, and their u e t eaded upperends a c e in t e p P at 2 by nuts 25, The note 2 are leea e n coun unkopenin s termed. in th up r fac o t e en plate 32 fer a eason which W111become obvious hereina er.

Each of the senior members is of identical construction and only onewill be described in detail. Each c rrier comprise .a rectaneularlyshaped body :21 3 and i) having end tongueelike portions 1Z1 slidab'lymounte n radially directed grooves 2.8 and 2:9 formed in the facingsurfaces of the end plates 23 and 23. Each carrier "body 21 is providedat its .outer edge with an enlarged head-like portion having therein alongitudinally extending channel which receives an abrastive unitincluding a channeled support 31 and a grinding stone 32 securedtherein. The abrasive unit is secured in the carrier channel by alongitudinally extending clamp block 33 held in place by screw studs 34.

The tool shown in Figs. 1 and 3 is adapted for the grinding of so-calledblind bores and, to this end, each carrier body 21 is provided with anoverhanging portion 21 which extends downwardly past the peripheral edgeof the lower end plate 23 which is shaped as shown in Fig. 4. That is tosay, the periphery of the bottom plate 23 is provided with alternatinghumps and depressions and the carrier body portions 21 overhang theperipheral edge of the depressed portions thereof. The hump portions ofthe bottom plate 23 receive the ends of the posts 24 whereby the postsare located in close proximity to the periphery of the end plates 22 and23 making the tool frame much more rigid so that it will transmit agreater torque without material distortion.

The carriers 25 are retained in the end plate grooves 23 and 29 by agarter spring 35 (Figs. 3 and 4) seated in grooves formed in the outeredge of the upper carrier tongue 21*- and by a garter spring 36 engaginghooks 31 secured by screws 38 to the overhanging carrier portions 2 hear e s 2 a e sup or ed at their er ed e by a central exp nd n ee e un tcomprising a stem 39 supporting a pair of cone elements 4t, 41 which enge in e mp em nt y aped notc s 42 formed the i ner edg s o the carrierbodies 21. A sleeve 43 is fixed in an opening i the bottom plate 23 andit slidably receives and supports the lower end of the cone stem 39. Thecones 40, 4| are prevented from rotating by a post 3% (Fig. 4) carriedby the end plates 22 and 23 and received in notches 39 in the cones. Thestem 39 extends upwardly through and beyond an enlarged opening 45 (Fig.3) in the top end plate 22 for cooperation with means for automaticallyexpanding the carriers 25 toward the cylinder wall, which isdiagrammatically illustrated at 46 (Figs. 1 and 3). The carriers areexpanded by movement of the stem 39 and. cones 40, 4| axially upwardagainst the slight pressure ofiered by the garter springs 35 and 36.When the stem 39 is moved downwardly the carriers are contracted ormoved away from the cylinder wall 43 through the action of the gartersprings 35 and 36. The mechanism for. moving the cone unit toautomatically expand the tool will ow be described.

The to l ex and n me s c des a two-part cam device comprising an upperannular and tubular cam element 41 having a depending socketelikeportion 48 with an opening 4,8 in its bottom through which the cone unitstem 39 slidably passes. The depending portion 48 of this cam element isalso ,slidably received in the opening 45 in the top end plate 22 sothat it is positively guided for axial slide movement along the stem 39by both the stem 39 and end plate 22. Rotation of cam element 41 isprevented by a key 49 carried in a slot formed in the upper I end plate22 and engaging a longitudinally ex.- tendin d o gat d keyw y .59 fo medn t adjacent exterior wall of the tubular porti n 48 of the cam element41 (Figs. 3, 7, 9 and 11).

:By f rm h c m emen a Just n'bed, it is p ov ded th a ce t al x al elona d socket 41 (Fi 3 in wh ch is re ive a c il d compression spr n 5. thou h which the eeri stem 9 p she stem 39 extends outwardly beyond epring 51 (Fi and its outer e is externally threaded at 333 to receive anadjusting nut 52. The spring 51, which extends outwardly beyond theupper end of the socket 41 is confined between the lower face of theadjusting nut .52 and the bottom of the socket 41. This arrangement issuch that, byscrewi-ng the nut 52 downwardly on the cone stem 39,

the spring 51 is compressed slightly due to the resistance offered bythe garter springs 35 and 33. This causes the cone stem 39 to moveupwardly and expand the carriers 25. More particularly, in the use ofthis tool, it may be inserted in the cylinder 43, as shown in Fig. 3,and

the nut 52 adjusted downwardly. This adjustment of the nut 52 pullscones 43 upwardly to expand the stonecarriers 25 to initially engage thestones 32 with the cylinder wall. After the grinding stones 32 areengaged with the cylinder wall, the spring 5| is loaded by the cam 41.As soon as the carriers engage the cylinder wall no further expansionoccurs until grinding takes place. However, after the carriers 25 haveengaged the cylinder wall one may, in using my invention, cause the toolto be automatically expanded during the grinding operation and thegrinding operation to be carried on under a predetermined unit stonepressure by further compressing the spring 51. By unit stone pressure, Imean the pressure applied over each square inch of grinding stone areain contact with the cylinder wall.

It is highly desirable, in order that best grinding results be obtained,that materials of difierent hardness be ground with varying unit stonepressures and that, in the grinding of a single cylinder ofpredetermined hardness, the tool marks and high points be initiallyremoved by rinding under a preliminary and much reduced stone pressure.If the full grinding pressure for the particular material being groundwere employed in removing tool marks and high points, the grindingstones would be rapidly broken down or injured to an extentv requiringreplacement thereof. For example, in the grinding of newly bored orformed cast iron and mild steel cylinders, I have found that a unitstone pressure of approximately five pounds may best be employed inremoving tool marks and high points and that the unit stone pressureemployed in finally grinding the cylinder should, preferably, vary fromtwenty to thirty pounds; whereas, in the grinding of cylinders formedfrom extremely. hard materials which require considerable pressure inorder that the abrasive grains may penetrate the surface being ground,the initial unit stone pressure may vary from five to ten pounds whilethe final pressure may vary from fifty to sixty pounds. In carrying outmy invention, the compression spring is so constructed thatpredetermined extents of compression of the same produce predeterminedspring loadings for causing the stone carriers to engage the cylinderwall under predetermined unit stone pressures. These spring loadings andunit stone pressures might be obtained in the tool so far described(Figs. 1 and 3) by adjusting the nut 52 downwardly on the cone stem 39to predetermined extents after the carriers have been adjusted intoengagement with the cylinder wall. However, the accuracy of such anadjustment would depend upon the care and skill of the operator and, inorder that the human element may be avoided and positive accuracy inadjustment may be insured, I provide an arrangement wherein the camelement 41' may be accurately shifted axially predeter mined extents,after the stone carriers have been set up initially against the cylinderwall. More specifically, a second annular cam element 53 (Figs. 1-3 and5-12) is mounted between the cam element 4'! and the upper face of thetop end plate 22, which lower cam element is mounted upon and guidedrotatably by the depending tubular portion 48 of the upper cam element41. The lower face of the upper cam element 41 (Fig. 6) is provided witha plurality of notches 54, each "ofwhich has an inclined camway 55 and avertical end wall 55 The lower cam element 53 is provided, on its upperface, with a similar number of notches 56 shaped complementally to thenotches 54, being provided with inclined camways 57 and vertical endwalls 51 The cam elements 41 and 53, in the normal, contracted conditionof the tool (Figs. 1 and 3), are disposed in a closed or fully nestedrelation with their cam faces 55and 5! engaged throughout and theirvertical notch walls 55 and 5! abutting.

The cam elements .41 and 53 are so constructed that by rotating thelower cam element 53 in a clockwise direction, as viewed in Figs. 1 and3,

the high points of the camways 51 of the lower cam element 53 are movedtoward the high points of the camways 55 of the upper cam element 41,and the upper cam element 41 is shifted axially upward, in turn,compressing the spring 5|.

It will be seen from the foregoing that a predetermined compression ofthe spring 5! effecting a predetermined spring loading and unit stonepressure may be accomplished by a predetermined rotation of the lowercam element 53. Therefore, having determined the desirable springloading for preliminary grinding to remove high points, etc., and havingdetermined the desirable loading for finally grinding either a cast ironor mild steel or a harder cylinder, the lower cam element 53 may berotated to a predetermined position and held there so that the tool willnot only be automatically expanded during the grinding operation, butsuch operation will be carried on under a selected unit stone pressure.

The lower cam element is held in its selected rotary position bylatching means. Specifically, the upper end plate 22 is provided with anopening 58 in which is received a ball 59 constantly urged upwardly by aspring 69. The underface of the lower cam element 53 is provided withfour notches or depressions 6|, 62, 63 and 64 located at spaced pointsin an arcuate path around the bottom of such element in alignment withball 59 so that, when the lower cam element is in its normal or homeposition (Figs. 1 and 3) the ball 59 is seated in the notch 6| yieldablyretaining the cam element 53 in that position. When the cam element 53is rotated clockwise from the position of Fig. 3, as will be permittedby the latch ball 60, and the notch 52 thereof comes into alignment withand receives the ball 59, the cam element 53 (Figs. 7 and 8) isyieldably latched and held in that position wherein the spring 5i iscompressed to an extent sufiicient to apply, for example, five poundsunit stone pressure. Then, by further rotating the cam element 53 untilthe ball 59 engages in the notch 53 (Figs, 9 and 10), the spring 5| isfurther compressed to exert a unit stone pressure of, for example,twenty pounds; and by rotating the cam element 53 to a position whereinthe ball 59 engages the notch 54 (Figs. 11 and 12), the spring is setfor exerting a unit stone pressure of, for example, sixty pounds. It ishighly desirable that the clockwise rotation of the lower cam element belimited so as to not pass beyond the maximum pressure notch 64 and, tothat end (Figs. 3 3 5, 8, 10 and 12), the upper end plate is providedwith an upwardly projecting pin 65 in the rotary path of and received inan arcuate notch 65 formed. in the lower face of the lower cam element53. As will be seen from Fig. 5, when the lower cam element 53 is in itsnormal at home position, the pin is at one end of the notch 55. As thecam element 53 is rotated clockwise, the

. pin moves along the notch 66, as indicated in Figs. 8 and 10, and, bythe time the cam element is rotated to its maximum pressure position,the pin 55 has reached the opposite end of the notch 66, as shown inFig. 12, preventing further rotation of the cam element.

In order that a single cylinder or successive cylinders may be ground topredetermined size with precision accuracy and with a minimum ofattention on the part of the operator, I provide means for limiting theexpansion of the tool, in turn, determining the amount or thickness ofmaterial to be removed from the cylinder wall. Specifically, theuniversal tool driving head 2!) is provided with an axial threadedopening w (Fig. 3) which receives a threaded shaft 6! having anadjusting head 89 on the lower depending end thereof. This head 59 isprovided on its upper inclined surface ill with a scale graduated inthousandths of an inch, and it also has a lower knurled portion H whichpermits ready adjust ment of the same. The head 6-9 is in axialalignment with the upper end of the cone stem 39 and the bottom of suchhead has a small rounded head or nose 12 adapted to abut the upper endof the stem 38. The ball head 20 supports an indicating element 13having a lower pointed end which registers with the scale F on theadjusting nut or head 69. It will be seen that by adjusting the nut 69toward and from the stem 39 the extent of axial movement of such stem iscontrolled or limited, in turn, controlling the extent of expansion ofthe abrasive carriers and the extent of grinding a cylinder.

In the use, assuming that .010" material is to be removed from a newlybored cast iron cylinder, the tool is placed in the cylinder asillustrated in Fig. l, and the adjusting nut 52 is screwed downwardlycausing the spring to move the cone unit to expand the abrasive carriersinto firm engagement with the cylinder wall as. The adjustment limitingor stop nut 69 is then screwed downwardly until it engages the end ofthe cone stem 39, after which the operator notes the position of thescale 19 relative to the indicating element l3 and then backs off the.nut 69 .910 as indicated on the scale Hi. It will be appreciated that inthe grinding of a cylinder the grinding stone wears away to a certainextent, say .095. Knowing this, the operator, in order to grind .010from the cylinder wall 46, backs off the adjustment limiting nut 59 anadditional .005. The lower pressure cam element 53 is next adjustedclockwise to its first position wherein the ball 59 seats in the notch62 in the lower cam element. When this is done the cone unit does notshift or expand the tool until grinding takes place, but the spring 5%is placed under a load causing the grinding stones 32 to engage the cylinder wall with, for example, a five pound unit stone pressure. The toolis now rotated, reciprocated and expanded in the bore for a short timeuntil the high points and tool marks are removed, whereupon the tool isstopped and the cam element 53 is adjusted to its second positionwherein the ball 59 engages the notch 63 in the lower face of the camelement. The grinding operation is then continued and, as grinding takesplace, the spring 51 moves the cone unit upwardly and expands thecarriers 25. During this operation, the spring 5| is under a substantialconstant load exerting a substantial constant unit stone pressure. Thecone stem 39 is eventually shifted to an extent wherein its upper endengages the nose l2 on the adjustment limiting nut (ill, preventingfurther expansion of the tool so that no further material is removedfrom the cylinder wall. When this has been done the cylinder has beenground .010".

To facilitate rotational movement of the lower cam element 53 againstthe action of the spring 5!, it is provided with a plurality of openings1 which are adapted to receive a suitable tool through which pressuremay be applied for rotating the cam element. As soon as the grindingoperation is completed, the tool may be collapsed by rotating the camelement in a counterclockwise direction back to its normal position ofFigs. 1 and 3. The tool in this condition is collapsed for ready removalfrom the cylinder. If it is desired to grind a plurality of cylinders tothe same size, all that the operator need do is to make a furtheradjustment in the adjustment lmiiting nut 69 to compensate for stonewear. The tool is then placed in the next cylinder, the lower camelement 53 set up to its different positions, and the cylinder ground asabove explained. In the event that a cylinder formed of a hardermaterial than cast iron or mild steel is to be ground, the cam element53 may be set up to the first position above explained for removing toolmarks and high points and then finally set up to its maximum positionwherein the ball 59 engages the notch E l in the lower face of thecamelement 53. In grinding such harder cylinders, the operation isotherwise the same as explained in connection with cast iron and mildsteel cylinders, except that in some cases grinding stones of differentcharacter may be substituted.

It will be appreciated that in the use of the foregoing tool a verygreat amount of torque must be absorbed through the stone carriers,'particularly when the tool is adjusted for final grinding pressures oftwenty pounds or more. In this type tool this torque is transmitted intothe stone carriers through the tongue-and-groove construction at the endthereof. Consequently, there is a constant tendency for the carriers todeflect during the grinding operation'and, in some cases, unless guardedagainst, this deflection may be sufficient to permanently distort orbind the carriers in their grooves and render them useless. In carryingout my invention, I utilize the end plate supporting parts 24 forpreventing any motional deflection of the carriers or deflection whichwould tend to permanently distort and injure the carriers.

More particularly, with the tool rotating in a clockwise direction, asviewed in Fig. 1, the drag imposed on the carriers by the cylinder walltends to deflect the carriers in a counterclockwise di rection. Itherefore mount each carrier 25 counterclockwise of one of the posts 24(Figs. 1 and 4) and in close proximity thereto. Each carrier body 21 isprovided with a central, elongated pad 15 disposed in alignment with theadjacent post 24 and long enough to remain in alignment with the postthroughout the range of adjustment of the carrier. The pads I5 are ofsuch thickness and the carrier bodies are so located that the outerfaces of the pads are spaced from the posts a distance of, for example,two to five thousandths of an inch. Deflection of the carrier bodies 2'!is greatest at the central part where the pads 15 are located and whenthe car rier bodies are deflected sufficiently for the pads 15 to engagethe posts 24, further deflection cannot take place. In this way,injurious deflection is prevented and the tool :body as a whole isrendered more rigid during the grinding operation.

While I have found that a tool of the foregoing construction well servesthe purposes of my invention, it will be understood that my inventionmay be embodied in tools of different formsfor example, the form shownin Figs. 13 to 15, inclusive. Referring particularly to Fig. 13, thismodified tool is quite similar to the tool previously described exceptfor the particular manner of driving the tool and the particular meansfor determining the extent of adjustment, the grinding pressure and theextent of the grinding operation.

More particularly, this modified tool comprises a cage-like frame havingend plates 80, 8| with radially directed grooves 82 in their facingsurfaces supporting end tongues 83* of abrasive carriers 83. Each of theabrasive carriers supports a grinding stone unit 84 similar to theabrasive unit of the first-described form, except that ad ditional meansis employed for positively preventing longitudinal displacement of theabrasive unit. Specifically, lugs are struck from the channel member 84(Figs. 13 and 15), which supports the grinding stone 84 at spaced pointsalong the length thereof. These lugs are rolled to form bead-likeelements 84 which seat in notches 8 1 formed in the adjacent wall of theabrasive unit supporting channel 94 and the block 84 which clamps theunit in place against outward displacement.

The carriers 89 (Figs. 13 and 15) are yieldably urged in contractingdirection by garter springs 85 applied to the opposite end portions ofthe carriers 83. The inner edges of the carriers are supported by atubular cone unit 86 having I thereon cone members 81, 88 and anupwardly extending tubular shank portion 89 slidably supported inacentral opening 99 in the upper end plate 99. The cone unit 86 isfurther supported .and guided for axial expansion movement by a centraltubular member 9| rigidly secured at its lower end to the bottom plate8|. The cone unit 89 is of such diameter as tosnugly receive the tubularmember 9i, the lower end of the tubular member 95 being of enlargeddiameter and having a laterally extending flange 92 received in a recess93 in the outer face of the lower end plate 9i, where it is secured byan annular series of screw studs 99. r

The tool of Fig. 13 is driven'from the lower end plate 8|. Specifically,I provide a spindle 95, the upper end of which is provided with a ballhead 96 forming part of a universaljoint 91 connected to a head 98 on aspindle of the so-called honing machine (not shown). The spindle 95 isof lesser diameter than and extends downwardly through the tubularmember 91, its lower end being provided with a ball 99. This ball end 99is provided with a diametrical pin lililwith oppositely extending endsreceived in diametrically opposed elongated slots lill formed in thelower end of the tubular member 9|. By enlarging the lower end of thetubular member 9| as above mentioned, there is provided a shoulder [02against which seats the shoulder 193 of a two-part thrust bearing ringltd having an annular arcuate bearing surface 495 against which the ballhead 99 seats. The ball head and spindle are retained in the tubularmember 9| by a nut I06 mounted in the lower, internally threaded end ofthe tubu lar member 9l'and having an annular bearing surface 19] againstwhich the lower endof the ball 99 seats. When the nut 106 is 'securedinplace, the ball head 99 is confined between it and the upper ring I94.'Theends of the'universal drive pin I99 are free to rock in onedirection due to the-length of the sljotslflhand they are also free torotate in a right-angular direction about the bearing surfaces I95 andI01, thereby providing a universal drive connection which, together withthe universal joint 91 at the other end of thespindleftlii, fullyaccommodates disalignmentbetween the grinding tool and its operatingmachine. r

The means for automatically expanding the abrasive carriers 83 is quitesimilar to that previously described. In this case (Figs. 13- and l4),I' provide an upper camielement I08 similar-to the cam elemental, exceptthatit is not pro vided with a depending tubular portion, but is merelymounted upon the cone unit 86 foraxial slide movement. To this latterend, the upper extending tubularpart 89 of the cone unit isprovided withan elongated slot I99 in which is received the-end of a pin H0 carriedby the m element I08. Between the cam element I08 and the upper endplate 89, I mount a lower cam element F I l which is similar to thelower cam element of the first-described form, which cam element ismounted rotatably upon the tubular portion 89 of the cone unit 96 and isadapted to be located in its normal home position and in its variouspressure-determining positions in the same manner as in the formpreviously described.

The adjusting mechanism of Figs. 13 and 14 furtherinciudes a pressurespring H2 confined between the upper cam element I98 and a pressureadjusting nut H3 threaded upon the upper exteriorly threaded end of thetubular portion 89 of the cone unit. 111 the use of this tool, the nutMS may be initially adjusted downwardly to expand the stone carriers 83into engagement with the cylinder wall, after which the lower camelement HE is rotated, as described in connection with the first form,to get the desired unit stone pressure. If desired, the unit stonepressure may be varied by screwing downwardly to a further extent theadjusting nut US after the abrasive carriers have been set against thecylinder wall. The extent to which the nut may be adjusted in thisinstance may be determined by the operator in any suitable manner.

In this modified form of tool (Figs. 13-15) I also provide an adjustmentlimiting means which includes an adjusting nut H5 threadedly engagedwith the upper end of the tubular member 9| and having a bead H6 on itsbottom face adapted to engage the upper end of the tubular portion 9| ofthe cone unit. This nut serves the same purpose in the same way as thnut 69 of the first form, the same being set after the abrasive membershave engaged the cylinder wall by moving it first into engagement withthe upper end of the cone unit 9! and then backing it away to an extentequal to the thickness of material to be removed from the cylinder wallplus stone wear. The extent of adjustment of this nut H5 may bedetermined by a scale II! on the lower part thereof which registers withan indicating element I [9 carried by a ring-like member I [9 secured tothe upper portion of the adjusting nut H3. Otherwise the constructionand operation of this form of my invention are similar to theconstruction and operation of the form previously described.

It is believed that the operation and advantages of my invention will bewell understood-from the foregoing description. My invention not onlyprovides a simple and inexpensive tool but one which is quite rugged anddurable. It is well suited for heavy duty work with precision results.The work to be done by the operator is reduced to the Very minimum.Accurate grinding pressures are obtainable without guesswork merely bysetting the adjustable cam device to different positions representingselected pressures. This arrangement greatly facilitates not only thegrinding of a single cylinder but successive cylinders. In the grindingof successive cylinders the only adjustment required is adjustment ofthe grinding limit stop to compensate for stone wear, after the grindingof the first cylinder. The grinding operation is further greatlyfacilitated by the readiness in which the tool may be applied to andremoved from a cylinder. After the grinding operation the onlyadjustment required to remove the toolis movement of the cam device toits home position. This can be done easily and quickly and when it isdone the-tool is conditioned for immediate insertion in a new cylinder.

I claim:

1. A cylinder grinding tool comprising a body, abrasive carriers mountedin said body for movement toward and from a cylinder wall to be ground,means for moving said abrasive carriers toward the cylinder wallincluding a member shiitable in a direction to so move said carriers, aspring compressible for shifting said member, an element carried by saidmember and adjustable therealong in one axial direction to initiallycompress said spring and shift said member to cause said carriers toinitially engage the cylinder wall, another element on said memberadjustable independently of said first element to compress and holdcompressed said spring to difierent selected extents after said carriersare initiallyengaged with the cylinder wall for effecting movement ofsaid carriers toward the cylinder wall under different selectedpressures during the grinding operation.

2 A cylinder grinding tool comprising a body, abrasive carrierssupported by said body for expansion and contraction movements, andmeans for automatically expanding said carriers prior to and during thegrinding operation which includes a member engaging said carriers andmovable in one direction to expand said carriers, compressible springmeans for urging said member in said one direction, and means forcompressing said spring means to variable extents for applyingpredetermined grinding pressures which includes devices at the oppositeends of said spring means, each of said devices being carried by saidcarrier-engaging member and being adjustable axially of said springmeans in opposite directions and independently of each other to effectindependent compression of said spring, and means for holding one ofsaid devices in any one of a plurality of predetermined positions forapplying predetermined grinding pressures.

3. A cylinder grinding tool comprising a body, abrasive carriers mountedin said body for movement toward and from a cylinder wall to be ground,means engaging said carriers and move able to move said carriers towardthe cylinder wall, and means for moving said carrier-moving means toautomatically move said carriers t9? Ward the cylinder wall including anelement car.- ried by and axially adjustable therealong and forming partof said carrier-moving meaILS, a Com v e, and a comp es ion sp in s dcam device having; two parts, one of which is adjust,- able rotatably tomove the other part aXially of said spring and having a plurality ofpositions, to compress the latter to different selected extents forexerting a predetermined grinding pressure.

A y inder r nding tool co p ising a body, abrasive carriers supported bysaid body for movement toward a cylinder wall to be ground, and meansfor moving said carriers toward the cylinder wall which includes amember engaging said carriers and movable axially of said body in onedirection, an adjustable element on said mem-v ber, a second elementmounted for adjustable slide movement only along said member, acompression spring adapted to be compressed :by adjustment of saidelements, and a third element mounted for rotation only and having cammeans engaging said second element and so constructed that as said thirdelement is rotated in one direction said second element is shiftedaxially of said spring to compress the latter to variable extents, andmeans for releasably latching said third ele ment in any one of aplurality of selected rotary positions to cause said spring to exert anyone of a plurality of selected grinding pressures.

5. A cylinder grinding tool comprising a body, abrasive carriers mountedin said body for movement toward and from the cylinder to be ground,means for moving said abrasive carriers toward the cylinder wallincluding shiftable expanding elements engaging said abrasive carriers,a member supporting said elements and movable to shift the latter, acompression spring for moving said supporting member in one direction,an element on said supporting member slidably movable in one directionrelative to said supporting member tov compress said spring,. meanshaving a I plus rality of predetermined positions for sliding said slidale element to predetermined selected extents to compress said spring formoving said supporting member under predetermined pressures, a d means.for limiting movement of said supportin m mber in one direction to limitthe extents? the. grinding operation.

6- A cyli der rinding tool comprising a body, abrasive carriers mountedin said body for move ment teward and from the cylinder to be ground,means fer moving said abrasive carriers toward he cylind r W ll nclu n epanding elements enga ng said a rasi e ca rier-s, a movable membersupporting said expanding elements and mova e o. shi he a ter to expandsaidcarriers, a ompr ssion spr n tending to. move said suppor ing membero hi t id expandin el m n s, moons adjus able o compress s d. spring tovary e p ssure unde wh ch s id suppor ing mem ber i mo od s i t sa d exand n elements, moans movable to. ny one o a plura ity oi position o adjs n said, d usta e means to compr s aid. sp ing t prede rmined select dexten s, and me ns. o e ea b y ho d n said ad.- iustine m ns. n any o eoi its adiu ted. positions o ma t ng any on a p u a ity of selectedgrinding pressures, i 7, cyl e g ing o oomp isins a ody, abrasiv a iersmou ted. in sa d b dy o movement o rd and f om he y ind r to b ground,means for'moving said abrasive carriers toward the cylinder wallincluding expanding elements ng in saidabrasive carriers, a movablemom-s ber supporting said expanding elements and movable to shii thelatter to expa a d ar iers, a compre sio spr n tending to o e said sportins. mem er h ft s d e pan i g ements, means, adiustable to compresssaid spring to vary the pressure under which said supporting member s,moved, to sh f said expanding ments, m ans movable to any one of aplurality of positions, for adj ing said adjustable mean o, compre s idspring to predetermined selected extents, means o r leasa'b'ly h ldnslsaid adjusti mo siin any one of its adjusted positionsfor'maintai'nin g any onev of a plurality of selected grinding presssures, and means for variably limiting'the-extent o ovom nt of sa mem eand; in. turn, "the extent ofv the grinding operation, j A

8. A cylinder grinding tool cg'rnprising'aj body', abrasive carriersmounted in said bqdyfiorfexpan i n and ontr n; mo mo tsjm nsj forexpanding saidabrasive carriers including a,

shiftabledevi ce having elements engaging; said carriers-to expand thelatter when said device'i's shifted-in one direction-, a compressionspring tending to shift saidf device, a first adjustable mean-ea secondadjustable means, one of said adjustable means beingadj-ustable topreliminarily compress-said spring to expand said carriersto initiallyengage acylinder wall, and the other e! said adjustable means includinga part adjustable to shift said other adjustable means and compress saidspring to predetermined extents to cause the grinding operation to takeplace under selected grinding pressures, and means for releasablyholding said adjustable part in any one of a plurality of adjustedpositions.

9. A cylinder grinding tool comprising a body, abrasive carriers mountedin said body for movement toward and from a cylinder wall to be ground,spring means engaging said carriers and yieldably urging the sameinwardly away from the cylinder wall, a stem member passing through saidbody, expanding elements on said stem member engaging said carriers andmoving the latter toward the cylinder wall in opposition to, said springmeans when said stem member is moved in one direction, means for movingsaid stem mem ber in said one direction which includes a member mountedon said stem member and adjustable axially thereof, a member slidablycarried by said stem member for axial shift movement only along saidstem member, a rotatable member having cam means which, upon rotation ofsaid rotatable member, shifts said slidable member axially of said stemmember, a compression spring adapted to be compressed by adjustment ofeither of said adjustable members and which, when placed undercompression, tends to move said stem member in a direction to move saidcarriers toward the cylinder wall, and means for latching said rotatablememberin a plurality of rotary positions wherein said spring iscompressed to predetermined and variable extents for exerting selectedgrinding pressures during the grinding operation. V

10. A cylinder grinding tool comprising a body, abrasive carriersmounted in said body for movement toward and from a cylinder to beground, means for moving said carriers toward the cylinder wall whichincludes a stem member passing through said body, elements on said stemengaging said carrier and expanding the latter when said stem is shiftedin one direction, an adjusting member on said stem, a two-part camdevice, one part of said device being slidably supported by said stemand the other part being rotatable about said one part and held againstlongitudinal displacement, said two parts of said cam device havingengaged cam faces so shaped that rotation of said rotatable part shiftssaid slidable part axially along said stem, a spring adapted to becompressed by adjustment of said adjusting member or said one part ofsaid cam device, means for releasably holding said rotatable cam part incertain ones of a plurality of rotatable positions for holding saidspring compressed to predetermined extents, the cam faces of said camparts being also shaped to limit rotation of said rotatable cam. part ina direction toward its normal non-spring-compressing condition, and stopmeans limiting the extent of rotation of said rotatable cam part in aspring compressing direction.

11. A cylinder grindin tool comprising a body, abrasive carriers mountedin said body for movement toward and from the wall of a cylinder to beground, a tubular member rigidly secured at its lower end to and passingcentrally through and beyond one end of said body, a carrier expandingdevice slidably mounted upon said tubular member and engaging saidcarriers to move them toward the cylinder wall, and means moving saiddevice to so move said carriers which includes a, member adjustablymounted on said device, a two-part member on said device, one part ofsaid two-part member being supported to shift axially only and the otherpart being supported to rotate only to shift said one part axially, anda compression spring carried by said expanding device, the arrangementbeing such that said first adjustable member is adjustable to compresssaid spring to shift said device to cause said carriers to initiallyengage the cylinder wall, and said two-part member is independentlyadjustable by rotation of said rotatable part thereof to furthercompress said spring to effect a predetermined grinding pressure.

12. A cylinder grinding tool comprising a body, abrasive carriersmounted in said body for movement toward and from the Wall of a cylinderto be ground, a tubular member rigidly secured to and passing centrallythrough and beyond one end ofsaid body, a carrier expanding deviceslidably mounted upon said tubular member and engaging said carriers tomove them toward the cylinder wall, and means moving said device to somove said carriers which includes a member adjustably mounted on saiddevice, a two-part member on said device, one part of said twopartmember being shiftable axially only and the other part being rotatableonly to shift said one part axially, and a compression sprin carried bysaid expanding device, said first adjustable member being adjustable tocompress said spring to shift said device to cause said carriers toinitially engage the cylinder wall, and said twopart member beingindependently adjustable by rotation of said rotatable part thereof tofurther compress said spring to effect a predetermined grindingpressure, and a member mounted on said tubular member in axial alignmentwith said expanding device and adjustable toward and from said expandingdevice to limit the extent of movement of the latter and in turn theextent of the grinding operation.

13. A cylinder grinding tool comprising a body, abrasive carrier mountedin said body for movement toward and from the wall of a cylinder to beground, a tubular member rigidly secured to one end of said body, asecond tubular member mounted upon and slidable along said first tubularmember, expander elements on said second tubular member engaging saidcarriers to expand the latter as said second tubular member is shiftedin one direction, and means for shiftin said second tubular member insaid one direction which includes a first member mounted on said secondtubular member and adjustable therealong, a second member rotatable uponsaid sec ond tubular member, a third member slidable along said secondtubular member and seated against said second member, said second andthird members having complemental abutting camways whereby rotation ofsaid second member moves said third member axially along said secondtubular member toward said first member, and a compression springmounted upon said second tubular member and compressed by adjustment ofsaid adjustable members to shift said second tubular member to expandsaid carriers and to exert a selected grinding pressure through saidcarriers.

14. A cylinder grinding tool comprising a body, abrasive carriersmounted in said body for expansion and contraction movements, shiftablemeans engaging said carriers to expand and contract the same as it isshifted, and means for shifting said shiftable means to expand saidcarriers which includes a compression spring which when compressed tendsto move said shiftable means in carrier expanding direction, a devicecarried by said shiftable means and supporting one end of said springand adjustable to compress said spring and effect initial engagementarse-id carriers with the cylinder wall, and another device carried bysaid shiftable means and seated upon said body for supporting the otherend of said spring and adjustable aftersaid carriers have been engagedwith. the cylinder wall to. further compress said spring to establish arange of expansion of said carriers as the grinding operation is carriedon and to cause said carriers to move toward the cylinder wall under apredetermined pressure, and means located in the axial path of saidshiftable: means and adjustable axially toward. and from the latter toengage said shiftable means with said axially adjustable means sooner orlater to limit the extent of shift of said shiftable means and theexpansion of said carriers.

15. A rotatable cylinder grinding tool comprising end plates havingradially extendin grooves in their facing surfaces, a plurality ofannularly disposed posts rigidly joining together said end plates in.spaced relation and defining radial passageways, abrasive carriersmounted in said passageways and having end portions slidably mounted insaid end plate grooves,- and means for limiting the extent of deflectionof saidcarriers during the grinding operation including: elements onsaid carriers disposed in close proximity to said posts and adapted toengage the latter upon a predetermined deflection of said carriers in adirection opposite the direction of rotation of the tool.

16. A rotatable cylinder grinding tool comprising end plates havingradially extending grooves in their facing surfaces, a plurality ofannularly disposed posts rigidly joining together said end plates inspaced relation and defining radial passageways, abrasive carriersmounted in said passageways each of said carriers having: arectangularly-shaped body portion and end portions slidably mounted insaid end plate grooves, abrasive stones carried by the outer edges ofsaid carrier bodies, carrier-expanding means engag ing the inner edgesof saidcarri'er bodies, means by which the tool may be rotatably driven,and means limiting the extent of deflection of said carrier bodiesincluding an abutment element on the rear side, with respect todirection of tool rotation, of each said carrier body adapted to abutsaid posts, respectively, upon a' s'lig-ht deflection of said carrierbodies in a direction opposite the direction of tool rotation.

17. A rotatable cylinder grinding tool comprising end plates havingradially extending grooves in their facing surfaces, a plurality ofannularly disposed posts rigidly joining together said end plates inspaced relation and defining radial passageways, abrasive carriersmounted in said passageways, each of said carriers having arectangularly shaped body portion and end portions slidably mounted insaid end plate grooves, abrasive stones carried by the outer edges ofsaid earrier bodies, carrier-expanding means engaging the inner edges ofsaid carrier bodies, means by which the tool may be rotatably driven,and means limitin the extent of deflection of each of said carrierbodies including an elongated pad element on the central part of therear side,- with respect to direction of tool rotation, of each saidcarrier body, said pad element being aligned with the adjacent one ofsaid posts, being thick enough to abuttingly engag said post upon slightdeflection of the central portion of said carrier body, and being longenough to so engage said post throughout the operating range ofexpansion of said carrier body.

CHARLES A. FULMER.

